1. Field of the Invention
The present invention relates to an electronic appliance and a voice signal processing method for use in the electronic appliance. More particularly, it relates to an electronic appliance which processes a voice signal output from an electronic appliance main body and a voice signal to be input into the electronic appliance, and a voice signal processing method for use in this electronic appliance.
2. Description of the Related Art
Electronic appliances such as television receiver, audio system and air conditioner presently used are usually controlled by touching an operation button of a main body or by using a remote controller (hereinafter referred to as the RC). In the former case, an operator has to come close to the main body of the electronic appliance as a control target. When the electronic appliance is distant from the operator, the control is very laborious. This problem is solved using the RC as in the latter case.
Once the RC is taken by hand, the apparatus can be controlled without moving. However, if the RC is not near to the operator, the operator has to find out a place where the RC is present and fetch the RC. However, in a case where the apparatus is not continuously controlled and it is desired to readily control any one operation, for example, in a case where a power supply only is turned on first of all, the operator feels troublesome. Furthermore, there often occurs a situation in which the use of the RC is desired but the RC is not found.
In Japanese Patent Application Laid-Open Nos. 03-54989 and 03-184497, a method is disclosed in which the electronic appliance is controlled with a clapping sound instead of the RC.
In a case where the electronic appliance is controlled with the clapping sound, there is a problem that the clapping sound is deafened with a sound output from the electronic appliance main body or a sound generated around the electronic appliance, and thus the electronic appliance cannot be controlled as desired. There is also a problem that the sound output from the electronic appliance main body is detected as the clapping sound, and thus an erroneous operation occurs.
In addition, in a case where the electronic appliance (e.g., a television receiver (hereinafter referred to as the television)) is controlled with the clapping sound, when a power supply of a television 1201 is tuned off as shown in (A) of FIG. 17, the control can normally be performed. On the other hand, when the power supply of the television 1201 is turned on as shown in (B) of FIG. 17, not only the clapping sound but also a voice (hereinafter referred to as a main body sound) of a program being watched or contents that are simultaneously output from a speaker 1202 are detected by a microphone 101. Therefore, the clapping sound is buried in the main body sound, and thus the control might be obstructed.
Moreover, the erroneous operation might be caused by the main body sound. For example, when clapping occurs in the program being watched, the clapping with a certain sound level or more is detected as a clapping sound, and the clapping might continue as much as the predetermined number of times to cause the erroneous operation.
To cope with this problem, when the power supply of the electronic appliance is turned on, the control with the clapping sound may be prohibited. In this case, an operation which can be performed with the clapping sound is limited to the control at a time when the power supply is turned off, for example, an operation of turning on the power supply. A range of application is reduced, and a large restriction is imposed on this function.